1. Field of the Invention
The present invention relates to an image forming device management system and method in which a center management device (or a center system) provides remote maintenance of a plurality of image forming devices, such as copiers and printers, which are connected to the center management device via a public switched telephone network by a data communication device within a customer system.
2. Description of the Related Art
An image forming device management system in which the center system carries out an automatic reception of usage data of a plurality of image forming devices, such as printers and copiers, in various customer premises, such as user offices or companies, through a data communication device linked to the center system via a public switched telephone network (PSTN) or the like is known.
In the image forming device management system of the above type, the center system receives, on a normal message date (for example, the fifth day of each month) for each of the respective image forming devices, a usage data of a corresponding one of the image forming devices via the telephone network by using a call sent by the data communication device or a call sent by the center system. The center system automatically issues a billing of a usage charge of the corresponding one of the image forming devices based on the usage data received by the center system.
In a conventional image forming device management system, each of the respective image forming devices usually transmits, on a monthly deadline date, the usage data from the data communication device to the center system via the telephone network. However, during long holidays (e.g., summer holidays) of the customer system, all the image forming devices of the customer system are often turned off for the purpose of economy and safety of the use. In such a case, the data communication device that connects the image forming devices to the telephone network is also turned off, and the transmission of the usage data of that month to the center system cannot be performed by the customer system. Even if the sales or service person is delivered from the center system to the customer system, the person never collects the usage data of the image forming device due to the off state of the customer system.
Further, in the conventional image forming device management system, the center system is sometimes turned off during long holidays of the center system or due to the system maintenance. In such a case, the reception of the usage data from the customer system cannot be achieved by the center system. The customer system sends a call to the center system at several times, in order to transmit the usage data to the center system, but the center system does not acknowledge the call in response due to the off state of the center system. The connection between the customer system and the center system via the telephone network is not established in such a case, and an error of the communication takes place. As the center system is not operating in such a case, it is impossible to request the sales or service person to visit the customer system. As a matter of course, the data communication device cannot perform the transmission of the usage data of that month to the center system. Hence, the center system cannot achieve the reception of the usage data of that month from the customer system.
By referring to FIG. 36A and FIG. 36B, a description will now be given of a usage data reception operation of a conventional image forming device management system. FIG. 36A shows a call management table of a data communication device, and FIG. 36B shows an error log of the data communication device.
In this conventional image forming device management system, the data communication device receives a monthly total copy count from a corresponding one of the image forming devices. When a transmission time of a monthly deadline date is reached, the data communication device sends a call to the center system in order to transmit the usage data of the corresponding image forming device to the center system. This calling operation is performed by the data communication device based on the contents of the call management table, as shown in FIG. 36A, which are retained in the data communication device.
In the call management table of FIG. 36A, the call destination is provided to specify a phone number of the center system facility. The maximum number of calls is provided to indicate a maximum number of calls that can be attempted by the data communication device in cases of the busy state or the off state of the center system or a communication error. The calling interval is provided to indicate a time interval (in seconds) between the current call and the following call. The number of call events is provided to indicate the number of calls that have actually been attempted by the data communication device. The number of call events is incremented by one every time the call from the data communication to the center system is repeated. In the example of FIG. 36A, the number of call events indicates that the call from the data communication device to the center system was already repeated six times.
In the above-described calling operation of the data communication device, when the number of call events is equal to or larger than the maximum number of calls after the maximum number of calls have been attempted, it is determined that a communication error has occurred due to no return of acknowledgement from the center system. In such a case, an error code “0-23”, indicating no return of acknowledgement, is written to a recording area of the error log, as shown in FIG. 36B, by the data communication device. Then, the data communication device terminates the communication.
Accordingly, during long holidays of the center system or the customer system, it is impossible for the above-described conventional management system to achieve the reception of the usage data by the center system and to achieve the transmission of the usage data by the customer system. In addition, it is also impossible for the conventional management system to request the sales or service person to visit the customer system during the long holidays. This will significantly increase the number of non-received usage data cases as well as the cost of communications between the customer system and the center system.